The typical job is accessible to only about 27 percent of its metropolitan workforce by transit in 90 minutes or less. Labor access varies considerably from a high of 64 percent in metropolitan Salt Lake City to a low of 6 percent in metropolitan Palm Bay, reflecting differences in both transit provision, job concentration, and land use patterns. City jobs are consistently accessible to larger shares of metropolitan labor pools than suburban jobs, reinforcing cities' geographic advantage relative to transit routing.

The suburbanization of jobs obstructs transit’s ability to connect workers to opportunity and jobs to local labor pools. Fortunately, some metro areas exhibit near ubiquitous transit coverage rates and enable their jobs to access over half of their local labor pools, proving that expanded transit networks and integrated land use decisions can improve transit's utility to employers. As metro leaders continue to grapple with limited financial resources, it is critical for transit investment decisions to simultaneously address suburban coverage gaps as well as disconnected neighborhoods. Those decisions should be made in concert with actors from other public agencies and the private sector.

Brookings has extensively examined this topic in the Missed Opportunity series. An earlier study highlighted how the typical metropolitan resident can reach only 30 percent of jobs in the metropolitan area via transit in 90 minutes.

However, I think the integrated land-use concept is too simplistic. And I am concerned that some rail proponents may use the study to justify building rail lines to nowhere or rail lines for economic development purposes. Our goal should be providing high-quality transit to all potential users. The U.S. is a large, diverse country and it is unrealistic to expect all geographic areas to have the same types of land-uses. Transit policy makers need to provide transit to the development patterns that we have not the development patterns that some want us to have. And many suburban developments, including compact mixed-use developments are poorly served by today's transit. The best way to increase and enhance transit service in most of these cities is with Bus-Rapid-Transit (BRT) not rail.

There are several reasons why rail may not be the best answer. First, most cities do not have the urban spatial structure to support it. The cities where fixed-rail really is most effective are places built before World War II. Why? Before World War II cars were rare. Since workers had to commute by rail or walk, people had to live within several miles of their workplace. However, in the U.S. only a small number of cities have this required density. And most of these places already have rail networks.

Post World War II cities developed around the car. Cities that have grown rapidly over the past 50 years such as Atlanta, Charlotte, Denver, Houston and Phoenix have significantly different urban spatial structures and significantly lower densities. New suburbs in places such as New York City and Chicago resemble sunbelt cities far more than they resemble Manhattan or Michigan Ave in Chicago. And in the New York metro area density can be deceiving. New York City is actually less dense than Los Angeles. While Manhattan is far denser than downtown Los Angeles, the suburbs are almost as sprawling as those of Atlanta or Houston. While Manhattan represents the past, the New York suburbs may represent the future.

While many U.S. cities are striving to increase their density, most compact cities have these densities as a result of external forces unrelated to transit. While many metro areas want densities similar to Paris or Barcelona, these cities have high living costs and in Paris’ case suburbs that have a density similar to metro Los Angeles. Super high-density areas are not at all similar to U.S. cities. As of the beginning of 2012, the five densest metro areas in the world are Dhaka, Bangladesh; Mumbai, India; Surat, India; Chittagong Bangladesh; and Hong Kong, China. Let’s examine Hong Kong and Mumbai. Hong Kong is an island near mainland China. The island, which was owned by the British until the late ‘90’s, had to become denser to add population. Any other type of expansion required moving into Chinese territory, which was politically unattainable for most of Hong Kong’s history. Mumbai is one of the poorest major cities in the world. Its density is a double-edged sword; in 2012 60% of its residents live in slums without sanitation or sewer. Neither of these situations resembles any metro area in the U.S. today.

Many rail proponents tout Portland as an example of a high-density city that coordinates land-use, economic development and transit. However, Portland is not that dense. Its urban area density of 3,528 ranks it 9th among cities in the Western U.S. Portland is less dense than Denver, Las Vegas, Sacramento, Salt Lake City and San Diego. And it has not been able increase its transit accessibility or its ridership. Despite building an extensive light-rail and trolley network, the percentage of commuters using transit decreased from 2.3% to 2.2% between 1983 and 2010.

The better solution is to create transit that actually serves the needs of the United States circa 2012 not circa 1912. This means expanding transit by using express bus, BRT, Vanpool, Carpool or demand response vehicle. We need to examine privatization efforts. We are much further behind in Public-Private-Partnerships than Europe or Canada. There is simply insufficient money to construct and operate all of the planned rail expansions. Greater use of BRT and PPPs is the only fiscally responsible way to fund transit. Transit in many U.S. cities is lacking. We need robust transit networks but we need to be able to pay for them in the future. There are many benefits from building transit systems that quickly transport people from point A to point B. But we need to be realistic about U.S. geography and development patterns and produce an economically sustainable transit network.